diff --git a/src/Kunstmaan/MultiDomainBundle/Twig/MultiDomainTwigExtension.php b/src/Kunstmaan/MultiDomainBundle/Twig/MultiDomainTwigExtension.php
index 17fac90699..0f32c0d876 100644
--- a/src/Kunstmaan/MultiDomainBundle/Twig/MultiDomainTwigExtension.php
+++ b/src/Kunstmaan/MultiDomainBundle/Twig/MultiDomainTwigExtension.php
@@ -35,7 +35,7 @@ public function getExtraData($key)
     {
         $extraData = $this->domainConfiguration->getExtraData();
 
-        if ($extraData[$key]) {
+        if (isset($extraData[$key])) {
             return $extraData[$key];
         }